Lithotripsy Angioplasty Devices and Methods

ABSTRACT

Medical devices and method for making and using medical devices are disclosed. An example method for treating a blood vessel may include disposing a medical device within the blood vessel at a position adjacent to a lesion. The medical device may include an elongate shaft having a distal end region, a balloon coupled to the distal end region, and an iron-containing fluid disposed within the balloon. The method may also include inflating the balloon to a first pressure, delivering a plurality of electromagnetic pulses to the iron-containing fluid, and inflating the balloon to a second pressure greater than the first pressure.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 62/488,387 filed on Apr. 21, 2017, the disclosureof which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure pertains to medical devices, and methods formanufacturing medical devices. More particularly, the present disclosurepertains to lithotripsy angioplasty devices and methods.

BACKGROUND

A wide variety of intracorporeal medical devices have been developed formedical use, for example, intravascular use. Some of these devicesinclude guidewires, catheters, and the like. These devices aremanufactured by any one of a variety of different manufacturing methodsand may be used according to any one of a variety of methods. Of theknown medical devices and methods, each has certain advantages anddisadvantages. There is an ongoing need to provide alternative medicaldevices as well as alternative methods for manufacturing and usingmedical devices.

BRIEF SUMMARY

This disclosure provides design, material, manufacturing method, and usealternatives for medical devices. An example method for treating a bloodvessel is disclosed. The method comprises: disposing a medical devicewithin the blood vessel at a position adjacent to a lesion, the medicaldevice comprising an elongate shaft having a distal end region, aballoon coupled to the distal end region, and an iron-containing fluiddisposed within the balloon; inflating the balloon to a first pressure;delivering a plurality of electromagnetic pulses to the iron-containingfluid; and inflating the balloon to a second pressure greater than thefirst pressure.

Alternatively or additionally to any of the embodiments above, theiron-containing fluid includes iron nanoparticles.

Alternatively or additionally to any of the embodiments above, at leastsome of the iron nanoparticles have a conical shape.

Alternatively or additionally to any of the embodiments above,delivering a plurality of electromagnetic pulses to the balloon moves atleast some of the iron nanoparticles toward a surface of the balloon.

Alternatively or additionally to any of the embodiments above, anelectrode is coupled to the shaft and positioned within the balloon, andwherein delivering a plurality of electromagnetic pulses to theiron-containing fluid includes activating the electrode.

Alternatively or additionally to any of the embodiments above, theballoon further comprises a reinforcing member.

Alternatively or additionally to any of the embodiments above, inflatingthe balloon to a first pressure includes inflating the balloon to apressure of 3-5 atmospheres.

Alternatively or additionally to any of the embodiments above, inflatingthe balloon to a second pressure greater than the first pressureincludes inflating the balloon to a pressure of 5-9 atmospheres.

A method for treating a blood vessel is disclosed. The method comprisesdisposing a lithotripsy angioplasty medical device within the bloodvessel at a position adjacent to a calcified lesion, the lithotripsyangioplasty medical device comprising: an elongate shaft having a distalend region, a balloon coupled to the distal end region, aniron-containing fluid disposed within the balloon, and an electrodecoupled to the shaft; inflating the balloon to a first pressure;transferring force from the balloon to the calcified lesion bydelivering electromagnetic pulses with the electrode to activate theiron-containing fluid; and inflating the balloon to a second pressuregreater than the first pressure.

Alternatively or additionally to any of the embodiments above, theiron-containing fluid includes iron nanoparticles.

Alternatively or additionally to any of the embodiments above, at leastsome of the iron nanoparticles have a conical shape.

Alternatively or additionally to any of the embodiments above,transferring force from the balloon to the calcified lesion bydelivering electromagnetic pulses with the electrode to activate theiron-containing fluid moves at least some of the iron nanoparticlestoward a surface of the balloon.

Alternatively or additionally to any of the embodiments above, theelectrode is positioned within the balloon.

Alternatively or additionally to any of the embodiments above, theballoon further comprises a reinforcing member.

Alternatively or additionally to any of the embodiments above, inflatingthe balloon to a first pressure includes inflating the balloon to apressure of 3-5 atmospheres.

Alternatively or additionally to any of the embodiments above, inflatingthe balloon to a second pressure greater than the first pressureincludes inflating the balloon to a pressure of 5-9 atmospheres.

A lithotripsy angioplasty medical device is disclosed. The lithotripsyangioplasty medical device comprises an elongate shaft having a distalend region; a balloon coupled to the distal end region; aniron-containing fluid disposed within the balloon; an electrode coupledto the shaft and positioned under the balloon, the electrode beingdesigned to deliver electromagnetic pulses; wherein the balloon isdesigned to shift between a first unexpanded configuration, a secondconfiguration when the balloon is partially expanded into contact with atarget region, and an expanded configuration.

Alternatively or additionally to any of the embodiments above, theiron-containing fluid includes iron nanoparticles.

Alternatively or additionally to any of the embodiments above, at leastsome of the iron nanoparticles have a conical shape.

Alternatively or additionally to any of the embodiments above, theballoon further comprises a reinforcing member.

The above summary of some embodiments is not intended to describe eachdisclosed embodiment or every implementation of the present disclosure.The Figures, and Detailed Description, which follow, more particularlyexemplify these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure may be more completely understood in consideration of thefollowing detailed description in connection with the accompanyingdrawings, in which:

FIG. 1 is a partial cross-sectional side view of an example medicaldevice.

FIG. 2 is a cross-sectional side view of a portion of a blood vessel.

FIG. 3 is a partial cross-sectional side view of an example medicaldevice disposed in a blood vessel.

FIG. 4 is a partial cross-sectional side view of an example medicaldevice disposed in a blood vessel.

FIG. 5 is a side view of an example medical device.

FIG. 6 is a partial cross-sectional side view of an example medicaldevice disposed in a blood vessel.

While the disclosure is amenable to various modifications andalternative forms, specifics thereof have been shown by way of examplein the drawings and will be described in detail. It should beunderstood, however, that the intention is not to limit the invention tothe particular embodiments described. On the contrary, the intention isto cover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the disclosure.

DETAILED DESCRIPTION

For the following defined terms, these definitions shall be applied,unless a different definition is given in the claims or elsewhere inthis specification.

All numeric values are herein assumed to be modified by the term“about”, whether or not explicitly indicated. The term “about” generallyrefers to a range of numbers that one of skill in the art would considerequivalent to the recited value (e.g., having the same function orresult). In many instances, the terms “about” may include numbers thatare rounded to the nearest significant figure.

The recitation of numerical ranges by endpoints includes all numberswithin that range (e.g. 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and5).

As used in this specification and the appended claims, the singularforms “a”, “an”, and “the” include plural referents unless the contentclearly dictates otherwise. As used in this specification and theappended claims, the term “or” is generally employed in its senseincluding “and/or” unless the content clearly dictates otherwise.

It is noted that references in the specification to “an embodiment”,“some embodiments”, “other embodiments”, etc., indicate that theembodiment described may include one or more particular features,structures, and/or characteristics. However, such recitations do notnecessarily mean that all embodiments include the particular features,structures, and/or characteristics. Additionally, when particularfeatures, structures, and/or characteristics are described in connectionwith one embodiment, it should be understood that such features,structures, and/or characteristics may also be used in connection withother embodiments whether or not explicitly described unless clearlystated to the contrary.

The following detailed description should be read with reference to thedrawings in which similar elements in different drawings are numberedthe same. The drawings, which are not necessarily to scale, depictillustrative embodiments and are not intended to limit the scope of theinvention.

The use of medical devices for balloon angioplasty may be a desirablemethod for treating intravascular lesions in a blood vessel. In someinstances, calcification along or otherwise adjacent to the vessel wallcan complicate an intervention. Disclosed herein are angioplasty devicesand methods that are designed to improve the treatment of intravascularlesions. The devices and methods disclosed herein may be described aslithotripsy angioplasty devices/methods in that the devices may transfera force to the treatment area to break up the lesion. Some additionaldetails are disclosed herein.

FIG. 1 is a partial cross-sectional side view of an example medicaldevice 10. The medical device 10 may include a catheter shaft 12. Insome instances, the catheter shaft 12 may include a first or outermember 14 and a second or inner member 16. A balloon 18 may be coupledto the catheter shaft 12. In some instances, the balloon 18 may includea distal waist 20, a body region 22, and a proximal waist 24. The distalwaist 20 may be coupled to the inner member 16. The proximal waist 24may be coupled to the outer member 14. In at least some instances, themedical device 10 may be an over-the-wire ormonorail/single-operator-exchange catheter. Accordingly, the innermember 16 may define a guidewire lumen along at least part of itslength. An inflation lumen, in fluid communication with the balloon 18,may be defined between the inner member 16 and the outer member 14. Inother instances, the medical device 10 may take the form of a fixed wirecatheter. Other constructions are contemplated.

In some instances, the balloon 18 may be structurally reinforced. Forexample, the balloon 18 may include a reinforcing member 29. Thereinforcing member 29 may be a layer of material disposed along theinner surface of the balloon 18, the outer surface of the balloon 18, orboth. In some instances, the reinforcing member 29 may include a braid(e.g., a fiber braid), coil, or the like. In some of these and in otherinstances, the reinforcing member 29 may be disposed along the innersurface of the balloon 18, the outer surface of the balloon 18, or beembedded between two layers of the balloon 18. The reinforcing member 29may provide additional structural support to balloon 18, which mayincrease the burst strength of balloon 18. In addition, the reinforcingmember 29 may fortify the balloon 18 so that particles (e.g., ironnanoparticles as disclosed herein) may engage the wall surface of theballoon 18 without piercing or otherwise bursting the balloon 18.

In at least some instances, the medical device 10 may be considered alithotripsy medical device and/or a lithotripsy angioplasty medicaldevice. For the purposes of this disclosure, a lithotripsy angioplastydevice may be understood to be a device designed to transfer forces to atarget region in a manner that may break apart the target region. In atleast some instances, the transfer of forces may occur in a repeatedmanner with waves or flurries of force that are meant to impact thetarget region. The repeated force transfers could occur in a regularmanner with equally spaced time intervals between transfers, or theforce transfers could occur with differing time intervals betweentransfers. While lithotripsy devices may be commonly associated withultrasound and/or ultrasonic waves, the lithotripsy angioplasty devicesdisclosed herein are not meant to be limited to ultrasound devices.Indeed, medical device 10 (as well as other medical devices disclosedherein) may use ultrasound and/or other force generators to transferforce to the target site.

The medical device 10 may include an iron containing fluid 26 disposedwithin the balloon 18. The iron containing fluid 26 may include a fluidbase such as saline, water, or the like, and a plurality of ironparticles suspending in or otherwise disposed within the fluid. The ironparticles may be considered to be iron nanoparticles (e.g., have a sizeon the order of about 1-100 nanometers), however this is not intended tobe limiting. The iron containing fluid 26 may be designed so that whenthe balloon 18 (e.g., and/or the iron containing fluid 26) is exposed toa magnetic field, the iron particles within the iron containing fluid 26may migrate within the balloon 18. In at least some instances, the ironparticles may migrate toward the surface of the balloon 18. When themagnetic field is pulsed, this may cause pulses of movement or forcewithin the balloon 18 that can be transferred to a target site such as acalcified lesion within a vessel. In some instances, magnetostrictiveparticles (e.g., such as Terfenol-D, Galfenol, or the like) may be addedto the iron containing fluid 26. The magnetostrictive particles mayenhance or otherwise cause vibration (e.g., vibration of the ironcontaining fluid 26 within the balloon 18) at an elevated frequency, forexample, when the iron containing fluid 26 is exposed to a magneticfield (e.g., a time-varying magnetic field). The magnetic field may becreated in a number of different ways. For example, an electrode 27 maybe coupled to the shaft 12 (e.g., to the inner member 16) and disposedwithin the balloon 18. Activation of the electrode 27 may generate themagnetic field. Alternatively, an external magnetic field generator maybe utilized to create the magnetic field.

FIGS. 2-6 illustrate the use of the medical device 10. For example, FIG.2 illustrates an example blood vessel 28. A calcified lesion 30 may bedisposed along the blood vessel 28. In this example, the calcifiedlesion 30 is shown within the wall of the blood vessel 28. However,other arrangements may be seen. For example, portions or all of thecalcified lesion 30 may be disposed along an inner surface of the bloodvessel 28. In some of these and in other instances, plaque, a stenosis,a fatty deposit, or other types of lesions may also be present withinthe blood vessel 28.

The medical device 10 may be advanced through the blood vessel 28 to aposition adjacent to the calcified lesion 30 as shown in FIG. 3. Whensuitably positioned, the balloon 18 may be partially inflated asschematically depicted in FIG. 4. Partially inflating the balloon 18 mayoccur by infusing an inflation media into the balloon 18 (e.g., via aninflation lumen that may be defined between the outer member 14 and theinner member 16. Partially inflating the balloon 18 may includeinflating the balloon 18 so that the balloon 18 comes into contact withthe wall of the blood vessel 28. This may include simply contacting thevessel wall or, in some instances, partially inflating the balloon 18may include partially expanding the blood vessel 28. In some instances,partially inflating the balloon 18 may include inflating the balloon 18to a first pressure that might be in the range of about 1-6 atmospheresor about 3-5 atmospheres.

With the balloon 18 partially inflated, the electrode 27 (and/or asuitable magnetic field generator) may be activated. Activating theelectrode 27, including pulsing the electrode in order to pulse themagnetic field, may create a force or pulses of force 32 that can betransferred to the calcified lesion 30. For example, the pulsed magneticfield may cause the iron particles within the iron containing fluid 26to migrate within the balloon 18, for example toward the surface of theballoon 18, so that pulses of force 32 may be transferred to thecalcified lesion 30. The transferred forces may contact and break up thecalcified lesion 30 as depicted in FIG. 4.

As indicated above, the iron containing fluid 26 may include a pluralityof nanoparticles, labeled in FIG. 5 with reference number 34. Thenanoparticles 34 may have a variety of shapes. Some of the shapescontemplated include conical, geometric (e.g., having 3, 4, 5, 6, 7, 8,or more sides either regularly disposed or irregularly disposed),rounded or circular, oval, irregular, or the like. In at least someinstances, the nanoparticles 34 may have a shape that allows thenanoparticles to protrude into the wall of the balloon 18 in a mannerthat deflects the wall of the balloon 18 in a corresponding manner.Thus, when the electrode 27 (and/or other magnetic field generators) isactivated, the nanoparticles 34 can migrate to the surface of theballoon 18 and protrude into the wall of the balloon 18. Theseprotrusions can engage the wall of the blood vessel (e.g., the bloodvessel 28) and help to break up the calcified lesion 30. The reinforcingmember 29 (e.g., best seen in FIG. 1) may help to fortify the balloon 18so that the protrusion of the nanoparticles 34 into the wall surface ofthe balloon 18 does not puncture the balloon 18.

With the calcified lesion 30 broken up, the balloon 18 may be furtherinflated to a second pressure, greater than the first pressure, to treatthe blood vessel 28 as shown in FIG. 6. In some instances, the secondpressure may be on the order of about 4-12 atmospheres or about 5-9atmospheres.

The materials that can be used for the various components of the medicaldevice 10 (and/or other medical devices disclosed herein) disclosedherein may include those commonly associated with medical devices. Forsimplicity purposes, the following discussion makes reference to thecatheter shaft 12 and other components of the medical device 10.However, this is not intended to limit the devices and methods describedherein, as the discussion may be applied to other similar tubularmembers and/or components of tubular members or devices disclosedherein.

The catheter shaft 12 and/or other components of the medical device 10may be made from a metal, metal alloy, polymer (some examples of whichare disclosed below), a metal-polymer composite, ceramics, combinationsthereof, and the like, or other suitable material. Some examples ofsuitable polymers may include polytetrafluoroethylene (PTFE), ethylenetetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP),polyoxymethylene (POM, for example, DELRIN® available from DuPont),polyether block ester, polyurethane (for example, Polyurethane 85A),polypropylene (PP), polyvinylchloride (PVC), polyether-ester (forexample, ARNITEL® available from DSM Engineering Plastics), ether orester based copolymers (for example, butylene/poly(alkylene ether)phthalate and/or other polyester elastomers such as HYTREL® availablefrom DuPont), polyamide (for example, DURETHAN® available from Bayer orCRISTAMID® available from Elf Atochem), elastomeric polyamides, blockpolyamide/ethers, polyether block amide (PEBA, for example availableunder the trade name PEBAX®), ethylene vinyl acetate copolymers (EVA),silicones, polyethylene (PE), Marlex high-density polyethylene, Marlexlow-density polyethylene, linear low density polyethylene (for exampleREXELL®), polyester, polybutylene terephthalate (PBT), polyethyleneterephthalate (PET), polytrimethylene terephthalate, polyethylenenaphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI),polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide(PPO), poly paraphenylene terephthalamide (for example, KEVLAR®),polysulfone, nylon, nylon-12 (such as GRILAMID® available from EMSAmerican Grilon), perfluoro(propyl vinyl ether) (PFA), ethylene vinylalcohol, polyolefin, polystyrene, epoxy, polyvinylidene chloride (PVdC),poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS50A), polycarbonates, ionomers, biocompatible polymers, other suitablematerials, or mixtures, combinations, copolymers thereof, polymer/metalcomposites, and the like. In some embodiments the sheath can be blendedwith a liquid crystal polymer (LCP). For example, the mixture cancontain up to about 6 percent LCP.

Some examples of suitable metals and metal alloys include stainlesssteel, such as 304V, 304L, and 316LV stainless steel; mild steel;nickel-titanium alloy such as linear-elastic and/or super-elasticnitinol; other nickel alloys such as nickel-chromium-molybdenum alloys(e.g., UNS: N06625 such as INCONEL® 625, UNS: N06022 such as HASTELLOY®C-22®, UNS: N10276 such as HASTELLOY® C276®, other HASTELLOY® alloys,and the like), nickel-copper alloys (e.g., UNS: N04400 such as MONEL®400, NICKELVAC® 400, NICORROS® 400, and the like),nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such asMP35-N® and the like), nickel-molybdenum alloys (e.g., UNS: N10665 suchas HASTELLOY® ALLOY B2®), other nickel-chromium alloys, othernickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-ironalloys, other nickel-copper alloys, other nickel-tungsten or tungstenalloys, and the like; cobalt-chromium alloys; cobalt-chromium-molybdenumalloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®, and the like);platinum enriched stainless steel; titanium; combinations thereof; andthe like; or any other suitable material.

In at least some embodiments, portions or all of the medical device 10may also be doped with, made of, or otherwise include a radiopaquematerial. Radiopaque materials are understood to be materials capable ofproducing a relatively bright image on a fluoroscopy screen or anotherimaging technique during a medical procedure. This relatively brightimage aids the user of the medical device 10 in determining itslocation. Some examples of radiopaque materials can include, but are notlimited to, gold, platinum, palladium, tantalum, tungsten alloy, polymermaterial loaded with a radiopaque filler, and the like. Additionally,other radiopaque marker bands and/or coils may also be incorporated intothe design of the medical device 10 to achieve the same result.

In some embodiments, a degree of Magnetic Resonance Imaging (MRI)compatibility is imparted into the medical device 10. For example, themedical device 10, or portions thereof, may be made of a material thatdoes not substantially distort the image and create substantialartifacts (e.g., gaps in the image). Certain ferromagnetic materials,for example, may not be suitable because they may create artifacts in anMRI image. The medical device 10, or portions thereof, may also be madefrom a material that the MRI machine can image. Some materials thatexhibit these characteristics include, for example, tungsten,cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®,PHYNOX®, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g.,UNS: R30035 such as MP35-N® and the like), nitinol, and the like, andothers.

It should be understood that this disclosure is, in many respects, onlyillustrative. Changes may be made in details, particularly in matters ofshape, size, and arrangement of steps without exceeding the scope of thedisclosure. This may include, to the extent that it is appropriate, theuse of any of the features of one example embodiment being used in otherembodiments. The invention's scope is, of course, defined in thelanguage in which the appended claims are expressed.

What is claimed is:
 1. A method for treating a blood vessel, the methodcomprising: disposing a medical device within the blood vessel at aposition adjacent to a lesion, the medical device comprising: anelongate shaft having a distal end region, a balloon coupled to thedistal end region, and an iron-containing fluid disposed within theballoon; inflating the balloon to a first pressure; delivering aplurality of electromagnetic pulses to the iron-containing fluid; andinflating the balloon to a second pressure greater than the firstpressure.
 2. The method of claim 1, wherein the iron-containing fluidincludes iron nanoparticles.
 3. The method of claim 2, wherein at leastsome of the iron nanoparticles have a conical shape.
 4. The method ofclaim 2, wherein delivering a plurality of electromagnetic pulses to theballoon moves at least some of the iron nanoparticles toward a surfaceof the balloon.
 5. The method of claim 1, wherein an electrode iscoupled to the shaft and positioned within the balloon, and whereindelivering a plurality of electromagnetic pulses to the iron-containingfluid includes activating the electrode.
 6. The method of claim 1,wherein the balloon further comprises a reinforcing member.
 7. Themethod of claim 1, wherein inflating the balloon to a first pressureincludes inflating the balloon to a pressure of 3-5 atmospheres.
 8. Themethod of claim 1, wherein inflating the balloon to a second pressuregreater than the first pressure includes inflating the balloon to apressure of 5-9 atmospheres.
 9. A method for treating a blood vessel,the method comprising: disposing a lithotripsy angioplasty medicaldevice within the blood vessel at a position adjacent to a calcifiedlesion, the lithotripsy angioplasty medical device comprising: anelongate shaft having a distal end region, a balloon coupled to thedistal end region, an iron-containing fluid disposed within the balloon,and an electrode coupled to the shaft; inflating the balloon to a firstpressure; transferring force from the balloon to the calcified lesion bydelivering electromagnetic pulses with the electrode to activate theiron-containing fluid; and inflating the balloon to a second pressuregreater than the first pressure.
 10. The method of claim 24, wherein theiron-containing fluid includes iron nanoparticles.
 11. The method ofclaim 10, wherein at least some of the iron nanoparticles have a conicalshape.
 12. The method of claim 11, wherein transferring force from theballoon to the calcified lesion by delivering electromagnetic pulseswith the electrode to activate the iron-containing fluid moves at leastsome of the iron nanoparticles toward a surface of the balloon.
 13. Themethod of claim 9, wherein the electrode is positioned within theballoon.
 14. The method of claim 9, wherein the balloon furthercomprises a reinforcing member.
 15. The method of claim 9, whereininflating the balloon to a first pressure includes inflating the balloonto a pressure of 3-5 atmospheres.
 16. The method of claim 9, whereininflating the balloon to a second pressure greater than the firstpressure includes inflating the balloon to a pressure of 5-9atmospheres.
 17. A lithotripsy angioplasty medical device, comprising:an elongate shaft having a distal end region; a balloon coupled to thedistal end region; an iron-containing fluid disposed within the balloon;an electrode coupled to the shaft and positioned under the balloon, theelectrode being designed to deliver electromagnetic pulses; wherein theballoon is designed to shift between a first unexpanded configuration, asecond configuration when the balloon is partially expanded into contactwith a target region, and an expanded configuration.
 18. The lithotripsyangioplasty medical device of claim 17, wherein the iron-containingfluid includes iron nanoparticles.
 19. The lithotripsy angioplastymedical device of claim 18, wherein at least some of the ironnanoparticles have a conical shape.
 20. The lithotripsy angioplastymedical device of claim 17, wherein the balloon further comprises areinforcing member.